| abstract |
Biuret group-containing polyisocyanates are produced having an isocyanate functionality of at least (4) are prepared by reacting polyisocyanates having a functionality of at least (2.8) with water as the biuretizing agent. Most preferably water is used as the sole biuretizing agent. The preparation is useful as a curing agent in crosslinkable coating compositions. The coating composition can be used as an automotive clearcoat over a conventional pigmented basecoat, or as a basecoat or monocoat or even as a primer or sealer when a suitable amount of pigment is incorporated therein. |